Break-off tool

ABSTRACT

A tubing break-off tool designed especially for adjusting the length of a thin walled tubular sleeve. The break-off tool includes an internal support for internally supporting the sleeve on one side of the plane along which it is to be severed and an external support for externally supporting the sleeve on the opposite side of the severance plane from the first internal support. An adjustment member is provided for controlling the spacing between the external and internal supports.

[45] Mar. 18, 1975 United States Patent King, Jr.

[54] BREAK'OFF TOOL FOREIGN PATENTS OR APPLICATIONS [76] Inventor King 3990 Y 959,606 6/1964 United Kingdom............... 29/280 Atlanta, Ga. 30342 a July 12, 1973 [22] Filed:

Primary ExaminerAndrew R. Juhasz Assistant Examiner-Le0n Gilden Appl. N01: 378,445

Attorney, Agent, or Firm-B. J. Powell Related US. Application Data Continuation-impart of Ser. No. 274,613, July 24, 1 1.. whi ia as uyati nr -na of 5. N

[57] ABSTRACT A tubing break-off tool designed especially for adjusting the length of a thin walled tubular sleeve. The break-off tool includes an internal support for inter- 882,126, 155. 4, 19691Tat. N0. 3,67 9,l09, vvhic l li s a comifiuauoiia pfi" arsrTNo. "71 1,386, March 7, 1968, abandoned ling the spacing between the external and internal supports.

[56] References Cited UNITED STATES PATENTS 3,712,302 1/1973 Burke et al. 225/5 5 Claims 10 Drawmg Figures BREAK-OFF TOOL CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of my copending application Ser. No. 274,613 filed July 24, 1972, for Tubing Break-off and Finishing Tool" which is a continuation-in-part of my application Ser. No. 882,126, filed Dec. 4, 1969, for Method and Apparatus for Severing Tubing, now U.S. Pat. No. 3,679,109, which is a continuation-in-part of my application Ser. No. 71 1,386, filed Mar. 7, 1968 for Fastener Adapter and Method, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to the severing of thin walled tubing and more particularly to the severing of thin walled tubular sleeves.

2. Discussion of the Prior Art Tubing has frequently been cut to length by circumferentially scribing the outside thereof until the tubing was severed. With very thin walled tubing or tubular sleeves, however, this technique was inadequate since the tubing collapsed or otherwise distorted under the force of the cutting tool. At first sight, it would appear that the break-off to length of thin walled tubing having circumferential grooves therearound would be a simple matter. Many trials and the use of many tool designs have proved this assumption erroneous because most break-off techniques deform and/or leave burrs on the end of the tubing.

SUMMARY OF THE INVENTION These and other problems and disadvantages associated with the prior art areovercome by the invention described herein in that very thin walled tubing or tubular sleeves can be severed without detrimentally distorting the tubing. The technique employed by the invention includes externally supporting the tubular sleeve on one side of and closely adjacent the path along which the sleeve is to be severed and internally supporting the sleeve on the opposite side closely adjacent the path along which the sleeve is to be severed so that the sleeve will break along the path as the supporting members are pivoted with respect to each other. An adjustment member is provided to appropriately locate the internal and external supports with respect to each other.

The apparatus of the invention includes a first tool which has a body carrying an internal support member which is insertable into the tubular sleeve from one end to internally support same and a spacer member which is designed to position the internal support member within the sleeve. A second tool which has step portions integral with each other in an end-to-end relationship is provided with each of the step portions having holes therethrough to support the sleeve about its exterior. The tools operate in conjuction with each other to break the sleeve along a weakened grooved section.

These and other features and advantages of the invention disclosed herein will become more clearly understood upon consideration of the following detailed description and accompanying drawings wherein like characters of reference designate corresponding parts throughout the several views and in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of one embodiment of the invention illustrating its operation;

FIG. 2 is a side view of the tool of the'invention shown partly in cross-section;

FIG. 3 is an enlarged end view of FIG. 2;

FIG. 4 is an enlarged partial side view showing the invention of FIG. 2 in use;

FIG. 5 is an enlarged partial side view of the tool of FIG. 2; and

FIGS. 6-10 illustrate the invention in use.

These figures and the following detailed description disclose specific embodiments of the invention, however, it is to be understood that the inventive concept is not limited thereto since it may be embodied in other forms.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS Referring to the drawings, it will be seen that the invention disclosed herein can be used to adjust any thin walled tubing to length. The invention is specifically designed for use in adjusting thin walled tubular sleeves such as those disclosed in applicants earlier application Ser. No. 71 1,386 to length. Such sleeves are designated S in the drawings. The sleeves S all have a tubular side wall W of a prescribed thickness usually in the order of 0.006 to 0.016 inch. The sleeves S may have a head flange for protruding head fasteners or for countersunk head fasteners, however, only head flanges F for countersunk fasteners are illustrated for sake of simplicity. Also, the side wall W has circumferential grooves G around the outside thereof as seen in the figures to facilitate the adjustment of the sleeves S to the grip length of a fastener (not shown). These grooves extend partly through the side wall W and may be spaced along the length of the side wall at predetermined intevals. The grooves G also lie in a plane substantially perpendicular to the axis of the sleeve. Of course, the inside diameter of side wall W is such that the bearing area of a fastener (not shown) would be snugly received therein.

The tool 10 is used in conjunction with a step plate member SP which is partially shown herein and described in detail in my co-pending application Ser. No. 274,613. The tool 10 comprises an elongate cylindrical body 11 defining a break-off working surface 12 at one end thereof and a removal working surface 14 at'the opposite end thereof. The body 11 is of a convenient length and diameter to be manually held and may be knurled as indicated at 15 to facilitate the gripping thereof.

A primary passage 16 as best seen in FIG. 2 is provided in that end of body 11 adjacent the break-off surface 12 and opens onto the surface 12. The centerline CL, of passage 16 is substantially normal to the surface 12. Passage 16 has a diameter d, and length L, as will become more apparent. A secondary passage 18 is also provided in that end of body 11 adjacent the break-off surface 12 and opens onto the surface 12. The centerline CL of passage 18 is parallel to the centerline CL of primary passage 16 as will become more apparent. Passage 18 has a diameter d and a length L as will be more fully explained. The edges of passages 16 and 18 are spaced apart an edge distance e which will also become more apparent. Internally threaded holes 19 and 20 respectively connect the passages 16 and 18 with the outside surface of body 11 and are oriented substantially perpendicular to the centerlines CL and CL of passages 16 and 18, the use of which will become more apparent.

A third passage 21 is provided in body 11 adjacent the removal surface 14 and opens thereon. The centerline CL of passage 21 is substantially normal to surface 14. The passage 21 has a diameter d and length L, as will become more apparent and an internally threaded hole 22 connects the passage 21 with the outside of body 11 and is substantially normal to the centerline CL An internal support member 30 is slidably received in the primary passage 16. The member 30 is cylindrical with a diameter d., just slidably receivable within the sleeve S as seen in FIG. 2. The diameter d of the passage 16 is such that the member 30 will be just slidably received therein. The length L of member 30 is such that the member can be positioned at any point within the sleeves S without the end of the sleeve abutting the surface 12. This will become more apparent. That portion of member 30 projecting over the break-off surface 12 is provided with an operating end surface 31 which is normal to the central axis A of the member 30 and defines a square shoulder 32 between the outside surface 34 and operating end surface 31 of member 30. It will also be noted that axis A coincides with the centerline CL of passage 16 when member 30 is in position as shown in FIG. 2. A set screw 35 threadedly received in hole 19 selectively locks the member 30 in position in passage 16. The length L of primary passage 16 is such that adequate support of member 30 is provided.

A spacer 40 is slidably received in the secondary passage 18 and projects out over the break-off surface 12. The spacer 40 has a convenient shape such as the cylindrical shape shown with a diameter d and a length L The diameter d of spacer 40 and the diameter d of the secondary passage 18 are such that the spacer 40 will be just slidably receivable in the passage 18. That portion of spacer 40 protuding over surface 12 is provided with an abutting end surface 41 illustrated substantially normal to the axis A: of passage 18 and the. length L of spacer 40 are such that the abutting end 41 can be movable positioned in the vicinity of the plane of end surface 31 of member 30 and selectively locked therein by set screw 42 threadedly engaged in hole 20. The adjustment of the abutting end 41 of spacer 40 with respect to the operating end 31 or support member 30 will be explained in more detail.

A removal rod 50 is slidably received in the third passage 21 of body 11 and selectively locked therein by set screw 51. The rod 50 is cylindrical with an outside diameter d at its main section 52 and a length L The diameter d is substantially equal to the outside diameter of sleeve S as will become more apparent. A reduced diameter pilot section 54 is formed on the protuding end of rod 50 with an outside diameter d, substantially equal to the inside diameter of sleeve S so as to be just slidable received therein. The main section 52 and pilot section 54 are concentrically arranged with an abutting shoulder 55 formed at their juncture.

As was explained in my previously filed copending application, the step plate SP has a series of step portions P integral with each other in an end-to-end relationship. The step portions P have different thicknesses corresponding to the spacing between the grooves G around the sleeves S. Appropriate passages are formed through each step portion of the step plate which have an outside diameter that conforms to and supports the sleeve S when it is inserted in the hole. The step plate SP has a straight working surface WS on one side thereof at which the sleeve S is to be broken or severed so that when the sleeve S is inserted through the appropriate passage in the step plate, the grooves G will be aligned with the working surface WS as seen in FIG. 4.

OPERATION Referring now to FIGS. 6-10, the operation of the invention will be more clearly understood. FIG. 6 shows the sleeve S ready for insertion through the step plate SP and the tool 10 ready for positioning in the sleeve S. In FIG. 7, the sleeve S has been inserted through the appropriate step portion of the step plate SP and the sleeve is manually held within the hole in the step plate so that the particular groove G in the sleeve at which it is to be broken or severed is aligned with and lies in the plane of the working surface WS. The internal support member 30 of the tool 10 has been inserted inside the sleeve S in FIG. 7 until the abutting end 41 of the spacer 40 has engaged the working surface WS of the step plate SP. The position of the abutting end 41 of the spacer 40 with respect to the operating end 31 of the internal support member 30 is such that when the abutting end 41 of the spacer 40 abuts the working surface WS of step plate SP, the operating end 31 of the internal support member 30 is located in alignment with the groove G in sleeve S at which it is to be broken or severed. This is best seen in FIGS. 4 and 5 and this position is usually such that the operating end 31 of the internal support member 30 protudes slightly beyond the abutting end 41 of the spacer 40 by the space s as seen in FIG. 5. It will also be noted that the edge distance e between the internal support member 30 and the spacer 40 is such that the wall thickness of the sleeve S will just be slidably received therebetween. The edge distance e is usually the wall thickness of the sleeve S plus a few thousandths clearance. It is desirable that the spacer 40 be located as close as possible to the sleeve S so that alignment is insured as well as the proper position of the operation end 31 of the internal support member 30.

As seen in FIG. 8, the tool 10 is pivoted so thatthe spacer 40 is moved away from the working surface WS of the step plate SP while the sleeve is still manually held within the step plate SP to cause the sleeve S to break along the groove G and to emanate from that point in the sleeve S which lies between the internal support member 30 and the spacer 40. After the sleeve has been partially broken as seen in FIG. 8, the tool 10 is then pivoted in the opposite direction as seen in FIG. 9 to complete the breaking or severing of the sleeve S along the groove G. The sleeve S is now adjusted to length with that portion of the sleeve S within the step plate SP being usually the one that is used. It should be pointed out, however, that the other portion of the sleeve that is on the internal support member 30 may also be used.

As illustrated in FIG. 10, the tool 10 is reversed and the removal rod 50 positioned so that the reduced diameter pilot section 54 thereof is received inside that portion of the sleeve S still within the step plate SP. The tool 10 is then moved toward the step plate SP so that the abutting shoulder 55 on the rod 50 engages the end of the sleeve S and forces the sleeve from within the step plate SP.

The diameter d of the spacer 40 is a convenient size. However, the diameter should be sufficiently small to prevent interference with the breaking or severing operation of the sleeve S. Further, the abutting end 41 of spacer 40 may be any convenient shape although the normal end 41 shown assures accurate positioning of the operating end 31 of the internal support member 30.

Thus, it will be seen that when the workman determines the proper length of the sleeve S to be used, he then selects the appropriate step portion of the step plate SP, inserts the sleeve S therethrough, breaks the sleeve at the appropriate groove with the tool 10, and then removes the broken sleeve S from the step plate so that it can be installed. It will be noted that a different step plate SP will be provided for each sleeve diameter and that a different too] would also be provided for each diameter.

While specific embodiments of the invention have been disclosed herein, it is to be understood that full use of substitutions, modifications and equivalents may be used without departing from the scope of the inventive concept.

I claim:

1. Apparatus for severing thin walled sleeves having at least one circumferentially extending narrow weakened portion therearound including:

an internal support member slidably receivable into the sleeve from one end thereof having an external configuration conforming to the internal configuration ofthe sleeve, said internal support member defining an operating end surface on the protruding end thereof oriented substantially normal to the central axis of said internal support member;

a support body carrying said internal support member;

positioning means carried by said support body and laterally spaced from said internal support member for selectively locating said internal support member within said sleeves, said positioning means including:

a spacer member carried by said support body having a central axis oriented substantially parallel to the central axis of said internal support member, laterally spaced from said internal support member sufficiently for the side wall of the sleeve to be slidably received therebetween, and defining an abuttment on the protruding end thereof, and

adjustment means for releasably locating said abuttment with said operating end surface of said internal support member; and,

a removal member carried by said support body and protruding therefrom, said removal member comprising a first section conforming in diameter and shape to the outside of the sleeve and a reduced diameter section integral with the protruding end of said first section and located coaxially therewith, said reduced diameter section having an outside diameter conforming to the diameter and shape of the inside of the sleeve, and an abuttment formed between said first section and said reduced diameter section so that when said reduced diameter sec tion lies within the sleeve, said abuttment will engage the end of the sleeve to move the sleeve.

2. Apparatus for severing thin walled sleeves having at least one circumferentially extending narrow weakened portion therearound including:

an internal support member slidably receivable into the sleeve from one end thereof having an external configuration conforming to the internal configuration of the sleeve;

a support body carrying said internal support member;

positioning means carried by said support body and laterally spaced from said internal support member for selectively locating said internal support member within said sleeves; and,

at least one step plate member comprising a series of step portions integral with each other in an end-toend relationship, said step portions increasing in thickness from one end of said plate member to the other, each of said step portions having a common straight bearing surface and a separate straight bearing surface opposed to said common surface and parallel thereto, each of said step portions defining at least one passage therethrough normal to said surfaces having a diameter just sufficiently large to receive the thin walled sleeves therethrough so that the sleeve is supported externally about the circumference thereof within said step plate member.

3. Apparatus for severing thin walled sleeves having at least one circumferentially extending narrow weakend portion therearound including:

an internal support member slidably receivable into the sleeve from one end thereof having an external configuration conforming to the internal configuration ofthe sleeve, said internal support member defining an operating end surface on the protruding end thereof oriented substantially normal to the central axis of said internal support member;

a support body carrying said internal support member;

positioning means carried by said support body and laterally spaced from said internal support member for selectively locating said internal support member within said sleeves, said positioning means including:

a spacer member carried by said support body having a central axis oriented substantially parallel to the central axis of said internal support member, laterally spaced from said internal support member sufficiently for the side wall of the sleeve to be slidably received therebetween, and defining an abuttment on the protruding end thereof, and

adjustment means for releasably locating said abuttment with said operating end surface of said internal support member; and,

at least one step plate member comprising a series of step portions integral with each other in an end-toend relationship, said step portions increasing in thickness from one end of said plate member to the other, each of said step portions having a common straight bearing surface and a separate straight bearing surface opposed to said common surface and parallel thereto, each of said step portions defining at least one passage therethrough normal to said surfaces having a diameter just sufficiently large to receive the thin walled sleeves therethrough so that the sleeve is supported externally about the circumference thereof within said step plate member.

4. Apparatus as set forth in claim 1 further including:

at least one step plate member comprising a series of step portions integral with each other in an end-toend relationship, said step portions increasingin thickness from one end of said plate member to the other, each of said step portions having a common straight bearing surface and a separate straight bearing surface opposed to said common surface and parallel thereto, each of said step portions defining at least one passage therethrough normal to said surfaces having a diameterv just sufficiently large to receive the thin walled sleeves therethrough so that the sleeve is supported externally about the circumference thereof within said step plate member.

5. Apparatus for severing thin walled sleeves having at least one circumferentially extending narrow weakend portion therearound including:

a support body defining a working surface thereon; an internal support member carried by said support body and projecting from said working surface, said internal support member defining an operating end surface on the protruding end thereof oriented substantially normal to the central axis of said internal support member and having an external configuration conforming to the internal configuration of the sleeve;

a spacer member carried by said support body and projecting from said working surface generally parallel to said internal support member, said spacer member spaced laterally of said internal support member a first prescribed fixed distance sufficient for the side wall of the sleeve to pass between said spacer member and said internal support member and defining an abuttment on the projecting end thereof; and,

adjustment means for selectively and releasably fixing said spacer member axially with respect to said internal support member to locate said abuttment with respect to the plane of said operating end surface of said internal support member;

further including an external support member defining a bearing surface thereon, and defining a passage therethrough opening onto said bearing surface having an axis substantially normal to said bearing surface, said passage having a diameter just sufficiently large to slidably receive the sleeve therethrough so that the sleeve is externally supported about its circumference and said abuttment contacts said bearing surface as said internal support member is inserted into the sleeve to locate said operating end surface within the sleeve. 

1. Apparatus for severing thin walled sleeves having at least one circumferentially extending narrow weakened portion therearound including: an internal support member slidably receivable into the sleeve from one end thereof having an external configuration conforming to the internal configuration of the sleeve, said internal support member defining an operating end surface on the protruding end thereof oriented substantially normal to the central axis of said internal support member; a support body carrying said internal support member; positioning means carried by said support body and laterally spaced from said internal support member for selectively locating said internal support member within said sleeves, said positioning means including: a spacer member carried by said support body having a central axis oriented substantially parallel to the central axis of said internal support member, laterally spaced from said internal support member sufficiently for the side wall of the sleeve to be slidably received therebetween, and defining an abuttment on the protruding end thereof, and adjustment means for releasably locating said abuttment with said operating end surface of said internal support member; and, a removal member carried by said support body and protruding therefrom, said removal member comprising a first section conforming in diameter and shape to the outside of the sleeve and a reduced diameter section integral with the protruding end of said first section and located coaxially therewith, said reduced diameter section having an outside diameter conforming to the diameter and shape of the inside of the sleeve, and an abuttment formed between said first section and said reduced diameter section so that when said reduced diameter section lies within the sleeve, said abuttment will engage the end of the sleeve to move the sleeve.
 2. Apparatus for severing thin walled sleeves having at least one circumferentially extending narrow weakened portion therearound including: an internal support member slidably receivable into the sleeve from one end thereof having an external configuration conforming to the internal configuration of the sleeve; a support body carrying said internal support member; positioning means carried by said support body and laterally spaced from said internal support member for selectively locating said internal support member within said sleeves; and, at least one step plate member comprising a series of step portions integral with each other in an end-to-end relationship, said step portions increasing in thickness from one end of said plate member to the other, each of said step portions having a common straight bearing surface and a separate straight bearing surface opposed to said common surface and parallel thereto, each of said step portions defining at least one passage therethrough normal to said surfaces having a diameter just sufficiently large to receive the thin walled sleeves therethrough so that the sleeve is supported externally about the circumference thereof within said step plate member.
 3. Apparatus for severing thin walled sleeves having at least one circumferentially extending narrow weakend portion therearound including: an internal support member slidably receivable into the sleeve from one end thereof having an external configuration conforming to the internal configuration of the sleeve, said internal support member defining an operating end surface on the protruding end thereof oriented substantially normal to the central axis of said internal support member; a support body carrying said internal support member; positioning means carried by said support body and laterally spaced from said internal support member for selectively locating said internal support member within said sleeves, said positioning means including: a spacer member carried by said support body having a central axis oriented substantially parallel to the central axis of said internal support member, laterally spaced from said internal support member sufficiently for the side wall of the sleeve to be slidably received therebetween, and defining an abuttment on the protruding end thereof, and adjustment means for releasably locating said abuttment with said operating end surface of said internal support member; and, at least one step plate member comprising a series of step portions integral with each other in an end-to-end relationship, said step portions increasing in thickness from one end of said plate member to the other, each of said step portions having a common straight bearing surface and a separate straight bearing surface opposed to said common surface and parallel thereto, each of said step portions defining at least one passage therethrough normal to said surfaces having a diameter just sufficiently large to receive the thin walled sleeves therethrough so that the sleeve is supported externally about the circumference thereof within said step plate member.
 4. Apparatus as set forth in claim 1 further including: at least one step plate member comprising a series of step portions integral with each other in an end-to-end relationship, said step portions increasing in thickness from one end of said plate member to the other, each of said step portions having a common straight bearing surface and a separate straight bearing surface opposed to said common surface and parallel thereto, each of said step portions defining at least one passage therethrough normal to said surfaces having a diameter just sufficiently large to receive the thin walled sleeves therethrough so that the sleeve is supported externally about the circumference thereof within said step plate member.
 5. Apparatus for severing thin walled sleeves having at least one circumferentially extending narrow weakend portion therearound including: a support body defining a working surface thereon; an internal support member carried by said support body and projecting from said working surface, said internal support member defining an operating end surface on the protruding end thereof oriented substantially normal to the central axis of said internal support member and having an external configuration conforming to the internal configuration of the sleeve; a spacer member carried by said support body and projecting from said working surface generally parallel to said internal support member, said spacer member spaced laterally of said internal support member a first prescribed fixed distance sufficient for the side wall of the sleeve to pass between said spacer member and said internal support member and defining an abuttment on the projecting end thereof; and, adjustment means for selectively and releasably fixing said spacer member axially with respect to said internal support member to locate said abuttment with respect to the plane of said operating end surface of said internal support member; further including an external support member defining a bearing surface thereon, and defining a passage therethrough opening onto said bearing surface having an axis substantially normal to said bearing surface, said passage having a diameter just sufficiently large to slidably receive the sleeve therethrough so that the sleeve is externally supported about its circumference and said abuttment contacts said bearing surface as said internal support member is inserted into the sleeve to locate said operating end surface within the sleeve. 